Forward link repeater delay watermarking system

摘要

A forward link repeater delay watermarking (FLRFWM) system and method that enable accurate position location of mobile stations in areas where repeaters are present by watermarking repeated signals with repeater information. A repeater watermarks a forward link signal with a (unique or non-unique) time delay modulation waveform watermark every time a signal passes through the repeater. A mobile station detects and/or identifies the time delay watermark on the forward link signal to determine repeater information that aids the network position determination entity or mobile station position location system in determining position location using AFLT and/or A-GPS systems. A forward link time delay watermarking system can be implemented to achieve low impact on FL and AFLT performance, favorable detection and identification probabilities, and short time-to-detect/identify.